Anycast manifest retrieval, unicast content retrieval

ABSTRACT

Provided is a content delivery method and architecture for delivering content from a node in a content delivery network (CDN) using an anycast address to direct a requesting device to access a content manifest. The manifest server of the CDN may select the provided manifest based on information received from the requesting device and/or any other network information, may alter attributes of the manifest itself, or direct the requesting device to a different device or manifest server of the CDN to obtain the manifest. The selection of the manifest, alteration of the manifest, or new location to obtain the manifest causes the connection for content to occur at one or more servers accessible through a unicast address, rather than an anycast address.

TECHNICAL FIELD

Aspects of the present disclosure involve content delivery networks, andmore particularly involve retrieving a content manifest using an anycastnetwork address, and then selecting a node of a content delivery networkwith a unicast address to retrieve the content where the selected nodeis based, in part, on the anycast node contacted to retrieve themanifest.

BACKGROUND

A content delivery network (CDN) is a sophisticated and large collectionof computers (e.g., content servers) and networking devices that is usedto deliver various forms of content, such as video, web pages, andimages, to devices over networks including the Internet. So, forexample, when a user operating a smart phone, laptop, tablet or othercomputing device requests a video to play on the device, a CDN may becontacted and deliver the video to the computing device where it isplayed. As more and more content is delivered over networks, refinementsand advances to CDNs, as well as the infrastructure supporting the CDN,are needed and happening constantly. Such advances involve reducingcost, increasing capacity, optimizing from where in the CDN content isdelivered and where it is stored to optimize delivery, among otherchallenges. Often an improvement in one area of the network may affectanother area of the network. It is with these issues in mind, among manyothers, that aspects of the present disclosure were conceived anddeveloped.

SUMMARY

One implementation of the present disclosure may take the form of amethod of serving content in a network. The method may include theoperations of receiving a request for a content manifest at a particularserving node associated with an anycast address, the particular servingnode being one of a plurality of manifest serving nodes associated withthe anycast address and the request comprising information of arequesting device in communication with the particular serving node,serving the content manifest to the requesting device, the contentmanifest based on the information of the requesting device in therequest, the content manifest comprising at least one unicast address ofa content delivery node suitable for delivering the content to therequesting device, and transmitting the content from the contentdelivery node associated with the unicast address to the requestingdevice.

Another implementation of the present disclosure may take the form of acontent delivery network (CDN). The CDN may include an anycast manifestserver receiving a request for a content manifest, the anycast manifestserver being one of a plurality of manifest serving nodes associatedwith an anycast address and the request comprising information of arequesting device in communication with the CDN and a unicast contentserver transmitting at least a portion of content file to a requestingdevice in communication with the unicast content server. Further, theanycast manifest server may provide the content manifest to therequesting device based on the information of the requesting device inthe request, the content manifest comprising at least one unicastaddress associated with the unicast content server.

Yet another implementation of the present disclosure may take the formof a server of a content delivery network (CDN). The server may includeat least one communication port for receiving a request for a contentmanifest from a content requesting device in communication with the CDN,the request for the content manifest received in response to a broadcastof an anycast address of the server and comprising information of thecontent requesting device, a processing device, and a computer-readablemedium connected to the processing device. The computer-readable mediumis configured to store information and instructions that, when executedby the processing device, performs the operations of serving the contentmanifest to the content requesting device based on the information ofthe content requesting device in the request, the content manifestcomprising at least one unicast address of a content delivery node ofthe CDN suitable for delivering the content to the content requestingdevice and transmitting the content from the content delivery nodeassociated with the unicast address to the content requesting device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an example network environment for distributing content to anend user from a network, such as a content delivery network (CDN).

FIG. 2 is an example network environment for distributing content to anend user from a network utilizing an anycast addressing scheme.

FIG. 3 is a system and method diagram illustrating a first examplemanifest and content delivery embodiment.

FIG. 4 is a system and method diagram illustrating a second examplemanifest and content delivery embodiment;

FIG. 5 is a flowchart of a method for utilizing a manifest server of aCDN with an anycast-type address; and

FIG. 6 is a computer architecture diagram illustrating one possiblesystem capable of implementing various aspects of the presentdisclosure.

DETAILED DESCRIPTION

Aspects of the present disclosure involve a content delivery method andarchitecture for delivering content from a node in a content deliverynetwork (CDN) using an anycast address to direct a requesting device toaccess a content manifest, also referred to herein as a manifest file.In one embodiment, a manifest server of the CDN may select the providedmanifest based on information received from the requesting device and/orany other network information. In other embodiments, the manifest servermay alter attributes of the manifest itself (manifest rewrite) or directthe requesting device to a different device or manifest server of theCDN to obtain the manifest. The selection of the manifest, alteration ofthe manifest, or new location to obtain the manifest causes theconnection for content, which may be chunks of content defined in themanifest, to occur at one or more servers accessible through a unicastaddress, rather than an anycast address. Thus, the original short livedconnection (or connections) to obtain the manifest from the manifestserver involves an anycast address. The information received from themanifest associated with the anycast address, alone or in conjunctionwith information about the device requesting the manifest, may then beused in establishing a unicast connection to obtain the content from acontent providing server.

Utilizing an anycast address to provide a manifest for a requestedcontent to a requesting device may provide several performanceadvantages to the CDN. For example, it is generally accepted thatshorting the distance between a content providing device and a receivingdevice may improve the speed at which the content is received. Thus,many CDNs attempt to select content servers that are geographically nearor logically near the requesting device to reduce the distance and timethat the content is transmitted through the CDN. However, the CDN maynot always know or otherwise determine where the requesting device islocated to select an advantageous content server. By providing amanifest through an anycast-type addressing scheme, a requesting devicemay access a manifest server that is geographically near the requestingdevice. Further, because requested content may be large and be providedfor several minutes or hours in a single session, selecting a contentserver that is not near the requesting device may negatively affect theperformance of the CDN. By providing the CDN with a mechanism foradapting or altering the manifest information based on receivedinformation from the requesting device, a more advantageous contentserver may be selected and provided in the manifest as an absoluteUniform Resource Locator (URL) to improve the performance of the CDN.Further, the selected content server may be accessed through aunicast-addressing scheme to prevent overloading at the particularcontent server of the CDN. In this manner, an anycast address for themanifest server may provide information of the location/type ofrequesting device, which the CDN may utilize to generate or alter amanifest file or direct the requesting device to a particular contentserver accessible through a unicast address to improve the performanceof the CDN.

FIG. 1 is a general network environment 100 for distributing content toone or more users through which a manifest server may be accessedthrough an anycast address and a content server may be accessed througha unicast address. The concepts of an anycast-addressing scheme and aunicast-addressing scheme are discussed in more detail below withreference to the network of FIG. 2. In general, the network environment100 of FIG. 1 provides a content delivery network (CDN) through whichcontent may be provided to a requesting device. In particular, thenetwork 100 receives a request for content from a user of the networkand determines a server or content providing component within thenetwork to provide the content to the user. Although illustrated in FIG.1 as a content delivery network 100, it should be appreciated thataspects of the present disclosure may apply to any type oftelecommunications network that utilizes IP addresses for connecting anend user to one or more components of the network. For example, aspectsof the disclosure may be utilized to connect a user of the network to anendpoint in the network, a conferencing server, a virtual privatenetwork device, and the like. Thus, although the CDN architecture isused throughout the document as the example network architecture throughwhich aspects of the present disclosure may be applied; other networkarchitectures and configurations are similarly contemplated.

In one implementation of the network environment 100, a CDN 102 iscommunicably coupled to one or more access networks 106. In general, theCDN 102 comprises one or more components configured to provide contentto a user upon a request and an underlying IP network through which therequest is received and the content is provided. The underlying IPnetwork associated with the CDN servers may be of the form of any typeIP-based communication network configured to transmit and receivecommunications through the network and may include any number and typesof telecommunications components. In this manner, CDN-based componentsmay be added to an existing IP-based communication network such that thecomponents receive a request for content, retrieve the content from astorage device, and provide the content to the requesting device throughthe supporting IP network. For simplicity, the use of the term “CDN”throughout this disclosure refers to the combination of the one or morecontent servers and the underlying IP network for processing andtransmitting communications, unless otherwise noted.

In one embodiment, a user device 104 connects to the CDN 102 through oneor more access networks 106 to request and receive content or contentfiles from the CDN. The access network 106 may be under the control ofor operated/maintained by one or more entities, such as, for example,one or more Internet Service Providers (ISPs) that provide access to theCDN 102. Thus, for example, the access network 106 may provide Internetaccess to a user device 104. In addition, the access network 106 mayinclude several connections to the IP network of the CDN 102. Forexample, access network 106 includes access point 120 and access point122. Also, the user device 104 may be connected to any number of accessnetworks 106 such that access to the CDN 102 may occur through anotheraccess network. In general, access to a CDN 102 (or underlying IPnetwork associated with the CDN) may occur through any number of ingressports to the CDN through any number of access networks. In yet anotherembodiment, the user device 104 may be a component of access network106.

In one embodiment, the CDN includes a directory server 110 that respondsto the request from the end user device 104 or access network 106 byproviding a network address (e.g., an IP address) where the contentassociated with the selected link can be obtained. In oneimplementation, the directory server 110 provides a domain name system(DNS) service, which resolves an alphanumeric domain name to an IPaddress. The directory server 110 resolves the link name (e.g., URL orother identifier) to an associated network address from which the userdevice 104 can retrieve the content. However, the requesting device 104may first obtain a manifest file from the CDN 102 that generallyincludes a uniform resource locator (URL) or a sequence of uniformresource identifiers (URIs) that identifies the locations of segments ofthe requested content. In other words, the manifest file lists orotherwise describes the segments of the requested content available fromthe CDN from which the requesting device may then obtain, through theDNS server 100, a particular content server within the CDN at whichthose segments are available.

In still another embodiment, a user of the user computing device 104enters a link name (e.g., URL or other identifier) into a browserexecuted on the computing device. The link name is associated with anetwork address within the CDN 102 at which the content may be obtainedand provided to the computing device. For example, the user of the userdevice 104 may enter a URL such as www.example.com/content into thebrowser of the computing device. Upon entering the URL, the hostname maybe extracted by the browser (www.example.com in this particular case)and sends a request (possibly via an operating system running within thecomputing device 104) to a domain name server (DNS) associated with theuser's access network 106. The DNS associated with the user's accessnetwork is known as the ISP resolver (shown best as access network DNS212 of FIG. 2). In one example, the DNS request transmitted to the ISPresolver from the computing device 104 includes the hostname of therequested content, as well as an IP address associated with thecomputing device.

In one implementation, the CDN 102 includes an edge server 112, whichmay cache content from another server to make it available in a moregeographically or logically proximate location to the user device 104.The edge server 112 may reduce network loads, optimize utilization ofavailable capacity, lower delivery costs, and/or reduce content downloadtime. The edge server 112 is configured to provide requested content toa requestor, which may be the user device 104 possibly via anintermediate device, for example, in the access network 106. In oneimplementation, the edge server 112 provides the requested content thatis locally stored in cache. In another implementation, the edge server112 retrieves the requested content from another source, such as a mediaaccess server (MAS) (e.g., a content distribution server 114 or acontent origin server 116 of a content provider network 118). Thecontent is then served to the user device 104 in response to therequests.

In addition, the CDN may broadcast to the access network 106 (or anyother access network) connected to the CDN information concerning thecontent serving nodes available in the CDN. In particular, the CDN maybroadcast Border Gateway Protocol (BGP) information about the accesspath to content serving CDN components. In general, BGP information (orBGP session, BGP feed or BGP data) is a table of Internet Protocol (IP)prefixes which designate network connectivity between autonomous systems(AS) or separate networks. BGP information for a network route mayinclude path, network policies and/or rule-sets for transmission alongthe path, among other information. The BGP feed may also includeInterior Gateway Protocol (IGP) information for network routes within anAS or network and/or other network information that pertains to thetransmission of content from the CDN. BGP uses Transmission ControlProtocol (TCP) as its transport protocol for exchanging routinginformation. Adjacent routers running BGP set up a TCP connection toexchange entire routing tables. Each router has enough information todetermine an optimal next hop to a destination.

As mentioned above, some components of the CDN 102 may be accessedthrough an anycast-routing scheme and some components may be accessedthrough a unicast-routing scheme. In general, “anycast” is a networkrouting technology that allows any number of possible nodes in a networkto service a request. In anycast, multiple network nodes capable ofservicing a request have the same network address—an anycast address.For example, FIG. 2 is an example network environment for distributingcontent to an end user from a network utilizing an anycast addressingscheme. The components of the network 200 of FIG. 2 are similar andoperate in a similar manner as those described above. Thus, a CDN 202 isprovided that is accessible to users 214, 216 through an access network204. Further, an access network DNS 212 (also referred to as an ISP DNS)is provided in the access network 202 and/or a CDN DNS 210 is providedin the CDN 202. In addition, content servers 206, 208 may be included inthe CDN 202, perhaps located in different geographic locations.

In the particular example shown, a content server 206 is located in oraround Houston, TX. and another content server 208 is located in oraround Denver, CO., although both content servers are a portion orcomponent of the CDN 202. As also shown, many user devices may accessthe CDN 202 through the access network 204, such as a user device 214located in Houston and another user device 216 located in Denver. Itshould be appreciated that manifest servers (discussed in more detailbelow) may also be included in the CDN 202 and disparately located indifferent geographic locations within the CDN. As a general rule, CDNsattempt to connect user devices 214, 216 to content servers and manifestservers 206,208 that are geographically near the user devices to reducethe distance that the content packets are transmitted through the CDNand access network 204.

As mentioned above, the DNS 210 returns an IP address of a contentserver of the CDN 202 from which content is available. Thus, eachcomponent 206,208 of the CDN 202 may announce an IP address for thecontent server through the BGP information that user devices 414,416 mayutilize to connect to those components. In other embodiments, theinformation may be provided through any announcement technique, such ason behalf of the components 206,208. As explained, “anycast” is anetwork routing technology that allows any number of possible nodes in anetwork to service a request. In anycast, multiple network nodes capableof servicing a request have the same network address—an anycast address.Therefore, due to routing protocols of the Internet and networks moregenerally, when a device requests data from an anycast address or sendsinformation to the anycast address, the request or the packets aredirected to one of the nodes associated with the address, and it isoften the closest node to the device. In particular, if the contentserver 408 in Denver announces an anycast address that the Denver-baseduser device 416 is searching for, the user device may connect to theDenver-based content server 408. Similarly, the Houston-based userdevice 414 may connect to a Houston-based content server 406, eventhough the content server in Houston 406 may announce the same anycastaddress that the content server in Denver 408.

However, because an anycast routing scheme tends to connect user devicesto content servers that are geographically near the user device,conventional anycast schemes tends to not work well for contentdistribution when there are large localized high traffic events, and inother situations. For example, when numerous users in some areasimultaneously requesting content (e.g., a live video stream), all ofthe requests may likely be directed to the node nearest theconcentration of users with the anycast address. In such cases, the nodemay be overwhelmed and not able to handle the volume of traffic causingperformance degradation for all of the users. If the node is thenremoved as a location for the anycast address, then the traffic, quitepossibly during a live session, will be rerouted to a different nodewhere the state of existing sessions will be lost and the congestionquite likely repeated at the new node

“Unicast”, in contrast, is a network routing technology that allows onenode in a network to service a request. So, unlike in anycast, theunicast address is associated with a particular node that the requestingdevice will connect to, e.g., for a TCP session, to obtain content. Withrespect to anycast or unicast, the term “node” is meant to refer to aserver or a collection of servers, which may in some specific examplesbe considered a cache or edge cache, and that are tasked with servingsome form of content in response to a request. Protocols exist fordetermining the best unicast address (node) to service any givenrequest.

One challenge in determining the best node involves ambiguity as to thelocation of the device making the request. In many conventional DNSresolution solutions, the IP address and identity of an ISP DNS resolver(such as DNS 212 of access network 204) and not the actual requestingdevice, is used to determine the node to service the request. However,many times the ISP DNS 212 is not a good proxy for identifying thelocation of the particular requesting device. Services and databases areavailable that associate IP addresses with geographical and other usefulinformation. However, in some instances, the node selected to handle therequest is distant from the requesting device, which may lead to variousinefficiencies in servicing the request including relatively longerlatency, dropped packets, greater expense, and the like, relative toselecting a unicast node more logically and/or geographically proximatethe requesting device.

Similar approaches may be implemented for accessing a manifest server ofa CDN. That is, a manifest server of the CDN 402 may announce a unicastaddress or an anycast address through which the requesting device mayrequest and obtain a manifest for the desired content. As mentionedabove, the manifest for a requested content generally includes a URL ora sequence of URIs that identifies the locations of segments of therequested content. In other words, the manifest file lists or otherwisedescribes the segments of the requested content available from the CDN402 from which the requesting device may then obtain a particularcontent server within the CDN at which those segments are available.However, due to conventional routing protocols, the initial connectionbetween the client device 416 and the manifest server 408 will mostlikely be at the logically geographically closest manifest server ableto service the request. However, the IP address of the requesting device416 will not likely be known. Thus, the anycast server receiving themanifest request can provide a useful data point or to the location inthe network of the requesting device without having any specificinformation about the requesting device itself.

In one particular embodiment of a CDN, the content servers may haveunique IP address, which may be unicast addresses. The manifest servers,in contrast, may share a common IP address, which may be an anycastaddress. The anycast address is advertised to components of networks incommunication with the manifest servers from each anycast node using adynamic routing protocol such as a BGP to enable those routers to makeintelligent routing decisions as to the best path.

Referring now to FIG. 3, a first example manifest and content deliverysystem and communication flow is illustrated. Many of the components ofthe system 300 of FIG. 3 are discussed above. In particular, the system300 includes a user device 304 that utilizes a browser 303 to requestand obtain content from a CDN. The CDN may include a DNS server 312,manifest servers 306 for storing and providing a content manifest, and acontent server 308 for providing the content. In some instances, the DNS312 may be an ISP DNS included in the user's access network. FIG. 3 alsoillustrates several communication exchanges between the components ofthe system 300 in accordance with the present disclosure.

Initially, the DNS 312 is provided with an anycast address for amanifest server 306 storing a manifest file associated with somecontent. So, for example, an anycast address for a video file accessibleover the CDN is provided to the DNS 312. More particularly, the userdevice 304 transmits a request to the DNS 312 for a location of amanifest file associated with a content file available through the CDN.In one example, the manifest request includes a URL for the requestedcontent. The DNS 312 resolves the request for the content and returns anaddress to a manifest server within the CDN at which the manifest forthe requested content is available. In one example, the returned addressis an anycast address that is common to more than one manifest server306 of the CDN.

The anycast address for the manifest server 306 may be, for example, anA or AAAA record (e.g., in IPv4 or IPv6 anycast address). In this firststep, the IP address of the user device 304, as well as otherinformation about the device, is often not available to the DNS system312. Note, contacting DNS 312 may involve several operations dependingon the DNS system and to what extent the DNS records are available atthe first device contacted or whether additional devices, such asauthoritative name servers, may also need to be queried. Nonetheless,when DNS addresses the request, it is usually a resolver address orinformation that is available to DNS. The resolver is a device orotherwise a service of the ISP serving the customer of the device, andthat is involved in interacting with DNS to obtain an IP address for therequesting client device.

Upon receiving the manifest address, the user device 304 then uses theanycast address to communicate with some device of the CDN to obtain themanifest. As mentioned above, one or more nodes of the CDN may have theanycast address. Moreover, those nodes may be logically and/orgeographically dispersed. Conventional network routing will typicallyconnect the requesting device 304 with the most efficient device (i.e.,the closest device) to service the request. Thus, the user device 304follows the anycast address to the manifest server 306 to request thecontent manifest. At this point in the sequence, the request made to themanifest server 306 will include information relevant to the requestingdevice as opposed to the resolver. For example, in establishing a TCPconnection with the anycast manifest server 306, the IP address of theuser device 304 may be available to the manifest server, as well asattributes about the device such as the operating system, the type ofdevice (mobile, etc.), the type of connection (e.g., wireless (e.g.,WiFi, 3G, 4G, and the like)) or wired, the speed of the connection, andother attributes. Further, the system 300 will know at which anycastdevice 306 the request was received. Such information may be utilized bythe system 300 to further facilitate providing the content to the userdevice 304.

As explained in more detail below, the anycast manifest server 306 mayselect and return 308 a manifest to the user device 304 based on theinformation received or derived from the manifest request. In anotherembodiment, the anycast manifest server 306 may create, rewrite, or edit308 a stored manifest file in response to the received information.Regardless, a manifest file (or portion of a manifest file) is returnedto the user device 304 by the manifest server 306. The manifest, eitherthrough methods to select the proper manifest or manifest rewriting,includes a unicast address, or more typically a sequence or collectionof unicast addresses, at which the actual content may be received fromone or more content servers 310. For content associated with a manifestfile, the manifest file defines a set of chunks that collectively makeup the content. For example, a video file may be a collection of chunksof the video. The manifest file also includes information as to how toaccess the chunks. For example, the manifest may include a collection ofURLs that contain location specific information to tell the DNS systemwhere the client is or the best location from which to serve thecontent. The DNS system may then pick a server and return a unicastaddress for the selected server. Alternatively, the manifest file mayinclude a collection of actual unicast addresses for each chunk. Hence,to play the video at a client device, the client device 304 (e.g., thebrowser 303 running on the client device) requests each chunk using theassociated unicast address from the CDN, whether based on resolving theassociated URLs or the IP addresses directly, and then plays the videousing the received chunks. Stated differently, for a video, the manifestmay reference or include several unicast IP addresses each related to achunk of the video. Using the manifest, the client device 304 accesses acontent server 310 of the CDN over a TCP connection to request a chunkof the file from the indicated content server using the unicast IPaddresses for each chunk, which are then each served from the device, ordevices, associated with the unicast IP addresses.

FIG. 4 illustrates a second example manifest and content delivery system400. Many of the components of the system 400 are similar or the same asthe system 300 of FIG. 3 discussed above. In particular, the system 400includes a user device 404 that utilizes a browser 403 to request andobtain content from a CDN. The CDN may include a DNS server 412, one ormore anycast manifest servers 406, one or more unicast manifest servers414, and one or more content servers 408 for providing the content. Inaddition, the system 400 also includes several communication exchangesbetween the components of the system in accordance with the presentdisclosure.

In this embodiment, the user device 404 requests content from the DNS412 as above and receives an anycast address for manifest servers 406 ofthe CDN. However, rather than providing the manifest to the user device404, the anycast server 406 may redirect the user device to a separateunicast manifest device 414. In other words, the anycast manifest server406 may identify some attribute of the request and provide informationfor another location or device of the CDN where the manifest may beretrieved. In one example, the manifest request may be redirected to adifferent address where the manifest is retrievable. The redirection maybe based on some attribute of the request or the location where theinitial request was received and may redirect the user device 404 to aunicast manifest server 414 that is based on the user device informationobtained from the manifest request. The unicast manifest server 414 maythen return the manifest that includes URL or other location informationfor content chunks at one or more content servers 410 of the CDN, asexplained above.

FIG. 5 is a flowchart of a method 500 for utilizing a manifest server ofa CDN with an anycast-type address. Thus, the operations of the method500 may be performed by the anycast manifest servers 306, 406 of FIGS. 3and 4 described above. It should be appreciated, however, that theoperations may be performed by any component of a telecommunicationsnetwork or CDN to provide a manifest for content to a requesting userdevice.

Beginning in operation 502, the anycast manifest server broadcasts ananycast IP address at which the manifest server may be reached. Itshould be appreciated that other manifest servers of the CDN may alsobroadcast the same anycast address. In one particular embodiment, theanycast address is broadcast utilizing BGP announcements or signalingprotocols. In operation 504, the manifest server receives a request fora manifest of a particular content from a user device. As explainedabove, the user device may receive the anycast manifest server addressfrom a DNS and follow the address to the anycast manifest server. Onceconnected, the user device may request a manifest for a particularcontent file available through the CDN.

In operation 506, the manifest server may obtain information of therequesting user device from the received manifest request. For example,the server may determine or estimate the IP address of the user device,as well as attributes about the device such as the operating system, thetype of device (mobile, etc.), the type of connection (e.g., wireless(e.g., WiFi, 3G, 4G, and the like)) or wired, the speed of theconnection, and other attributes. The manifest server may also accessone or more databases to determine attributes of the user device. Usingthe example of the IP address of the user device, the manifest servermay access a database of known or estimated geographic locations ofdevices with known IP addresses to estimate a location of the userdevice. In general, any information included in the request and/oravailable from one or more databases of user information may be utilizedby the manifest server to determine certain attributes about the userdevice.

With the obtained or derived information of the user device, themanifest server may provide a manifest, edit a manifest, or redirect theuser device to another manifest server. For example, if there are threeanycast manifest servers dispersed in different geographical locationsof the CDN, there may be three associated manifests that tie contentrequests within the manifest based on the geographical location of theanycast servers. In such an arrangement, in a first geographicallocation, say New York, the associated manifest may include a collectionof location-specific URLs associated with content chucks at a contentdelivery node in the New York region, whereas in a second geographiclocation, say Denver, the associated manifest may include a collectionof IP addresses associated with content chucks at a content deliverynode in the Denver area. Thus, if the request is received at the NewYork anycast server, the New York orientated manifest is selected andreturned to the device. Similarly or additionally, if the IP address ofthe requesting device is linked with New York, then that information maybe used to also select the New York manifest. Further, the combinationof information may also be used. Similarly but alternatively, fieldswithin the manifest may be rewritten or edited. So, rather thandifferent selectable manifests, fields within the manifest may berewritten based on the request. Thus, the unicast address for a contentserver in New York or the unicast address for the content server inDenver, may be written to the manifest based on the anycast serverreceiving the request and/or the IP address of the device requesting themanifest. In other words, the manifest server may attempt to associate ageographic location with the requesting device and select or alter amanifest that relates the estimated geographic location of the userdevice. This operates to connect the user device to potentially localcontent servers from which the chunks of the content may be provided.

In another embodiment, the manifest server may provide a redirectinstruction to the requesting user device to direct the device to aunicast manifest server based on the user device information. Thus, theanycast manifest server may determine that a unicast manifest server isbest selected to provide the manifest to the user device and direct theuser device accordingly. In general, the editing or selecting of amanifest or redirecting of the requesting device to another manifestserver may occur based on any information obtained or derived by themanifest server. For example, the anycast manifest server may estimate ageographic location of the requesting device and select a particularmanifest to connect the device to content servers that are near therequesting device. In another example, the anycast manifest server mayedit a manifest for a content to include identified content servers thatare near the requesting device. In yet another example, the anycastmanifest server may incorporate a load balancing of the content serversof the CDN to prevent any one server from servicing too many contentrequests. Also, the anycast manifest server may consider certain networkstructuring to determine which content server to include in the manifestor which unicast manifest server to redirect the user device. Ingeneral, any information of the user device, the network, or thereceived request may be utilized to select or edit a manifest ormanifest server.

In yet another embodiment, the manifest server may edit the manifest toinclude information that may be used by other components of the CDN tomake decisions on which content server to connect the user device. Forexample, the manifest may be edited to insert the user device's IPaddress into the hostname portion of the URLs included in the manifest.The components of the network may then be programmed or configured toextract this IP address from the URLs when received from the user deviceand use that information to determine or select a content server toprovide the content. In general, any edits or information may beincluded in the manifest by the manifest server to control theconnection of the user device to the CDN to provide the requestedcontent to the device.

Through the systems and methods discussed above, an anycast manifestserver may be provided in a CDN to provide a manifest to a requestingdevice through the anycast address. The manifest server of the CDN mayselect the provided manifest based on information received from therequesting device and/or any other network information, may alterattributes of the manifest itself (manifest rewrite), or direct therequesting device to a different device or manifest server of the CDN toobtain the manifest. The selection of the manifest, alteration of themanifest, or new location to obtain the manifest causes the connectionfor content, which may be chunks of content defined in the manifest, tooccur at one or more servers accessible through a unicast address,rather than an anycast address. Thus, the original short livedconnection (or connections) to obtain the manifest from the manifestserver involves an anycast address. The connection to the manifestserver associated with the anycast address, alone or in conjunction withinformation about the device requesting the manifest, may then be usedin establishing a unicast connection to obtain the content from acontent providing serve

FIG. 6 is example schematic diagram of a computing system 600implementing a server, client device, or other compute system configuredto execute or implement the methods or system components discussedherein. The computing system, which may include an application 608 withinstructions for implementing the methods discussed herein, includes abus 601 (i.e., interconnect), at least one processor 602 or othercompute element, at least one communication port 603, a main memory 604,a removable storage media 605, a read-only memory 606, and a massstorage device 607. Processor(s) 602 can be any known processor, suchas, but not limited to, an Intel® based processor(s), AMD® processor(s),or other various types of processors, cores, and the like. Communicationport 603 can be a 10/100 Ethernet port, a Gigabit port using copper orfiber, or a USB port or other type of port Communication port(s) 603 maybe chosen depending on a network such as a Local Area Network (LAN), aWide Area Network (WAN), or any network to which the computer system 600connects. The application may be in communication with peripheraldevices (e.g., display screen 630, input device 616 via Input/Output(I/O) port 609).

Main memory 604 can be Random Access Memory (RAM) or any other dynamicstorage device(s) commonly known in the art. Read-only memory 606 can beany static storage device(s) such as Programmable Read-Only Memory(PROM) chips for storing static information such as instructions forprocessor 602. Mass storage device 607 can be used to store informationand instructions. For example, hard disks such as the Adaptec® family ofSmall Computer Serial Interface (SCSI) drives, an optical disc, an arrayof disks such as Redundant Array of Independent Disks (RAID), such asthe Adaptec® family of RAID drives, or any other mass storage devices,may be used.

Bus 601 communicatively couples processor(s) 602 with the other memory,storage and communications blocks. Bus 601 can be a PCI / PCI-X, SCSI,or Universal Serial Bus (USB) based system bus (or other) depending onthe storage devices used. Removable storage media 605 can be any kind ofexternal hard drives, thumb drives, Compact Disc-Read Only Memory(CD-ROM), Compact Disc-Re-Writable (CD-RW), Digital Video Disk-Read OnlyMemory (DVD-ROM), etc.

Embodiments herein may be provided as a computer program product, whichmay include a machine-readable medium having stored thereon instructionswhich may be used to program a computer (or other electronic devices) toperform a process. The machine-readable medium may include, but is notlimited to, optical discs, CD-ROMs, magneto-optical disks, ROMs, RAMs,erasable programmable read-only memories (EPROMs), electrically erasableprogrammable read-only memories (EEPROMs), magnetic or optical cards,flash memory, or other type of media/machine-readable medium suitablefor storing electronic instructions.

As shown, main memory 604 is encoded with an application 650-1, whichmay include functionality described herein and that supportsfunctionality as discussed above and as discussed further below. Forexample, in one embodiment, the application 650-1 may include orotherwise implement the various processes and/or instructions describedherein. The application 650-1 (and/or other resources as describedherein) can be embodied as software code such as data and/or logicinstructions (e.g., code stored in the memory or on another computerreadable medium such as a disk) that supports processing functionalityaccording to different embodiments described herein. During operation ofone embodiment, processor(s) 602 accesses main memory 604 via the use ofbus 601 in order to launch, run, execute, interpret or otherwise performthe logic instructions of the 650-1.

The description above includes example systems, methods, techniques,instruction sequences, and/or computer program products that embodytechniques of the present disclosure. However, it is understood that thedescribed disclosure may be practiced without these specific details. Inthe present disclosure, the methods disclosed may be implemented as setsof instructions or software readable by a device. Further, it isunderstood that the specific order or hierarchy of steps in the methodsdisclosed are instances of example approaches. Based upon designpreferences, it is understood that the specific order or hierarchy ofsteps in the method can be rearranged while remaining within thedisclosed subject matter. The accompanying method claims presentelements of the various steps in a sample order, and are not necessarilymeant to be limited to the specific order or hierarchy presented.

The described disclosure may be provided as a computer program product,or software, that may include a machine-readable medium having storedthereon instructions, which may be used to program a computer system (orother electronic devices) to perform a process according to the presentdisclosure. A machine-readable medium includes any mechanism for storinginformation in a form (e.g., software, processing application) readableby a machine (e.g., a computer). The machine-readable medium mayinclude, but is not limited to, magnetic storage medium, optical storagemedium (e.g., CD-ROM); magneto-optical storage medium, read only memory(ROM); random access memory (RAM); erasable programmable memory (e.g.,EPROM and EEPROM); flash memory; or other types of medium suitable forstoring electronic instructions.

It is believed that the present disclosure and many of its attendantadvantages should be understood by the foregoing description, and itshould be apparent that various changes may be made in the form,construction and arrangement of the components without departing fromthe disclosed subject matter or without sacrificing all of its materialadvantages. The form described is merely explanatory, and it is theintention of the following claims to encompass and include such changes.

While the present disclosure has been described with reference tovarious embodiments, it should be understood that these embodiments areillustrative and that the scope of the disclosure is not limited tothem. Many variations, modifications, additions, and improvements arepossible. More generally, embodiments in accordance with the presentdisclosure have been described in the context of particularimplementations. Functionality may be separated or combined in blocksdifferently in various embodiments of the disclosure or described withdifferent terminology. These and other variations, modifications,additions, and improvements may fall within the scope of the disclosureas defined in the claims that follow.

What is claimed is:
 1. A method of serving content in a network comprising: receiving a request for a content manifest at a particular serving node associated with an anycast address, the particular serving node being one of a plurality of serving nodes associated with the anycast address and the request comprising information of a requesting device in communication with the particular serving node; identifying, by the particular serving node, a separate unicast manifest device based on the information of the requesting device in the request, the separate unicast manifest device being one of a plurality of content manifest devices; redirecting, by the particular serving node, the request to the separate unicast manifest device; and serving a content manifest to the requesting device by the separate unicast manifest device, the content manifest based on the information of the requesting device in the request, the content manifest comprising at least one unicast address of a content delivery node suitable for delivering the content to the requesting device.
 2. The method of claim 1 further comprising: establishing the anycast address with a domain name service (DNS) infrastructure for the content manifest associated with the content.
 3. The method of claim 1 wherein serving the content manifest comprises: selecting the content manifest from a plurality of content manifests associated with the content, the selection based on the information of the requesting device in the request for the content manifest.
 4. The method of claim 3 wherein serving the content manifest further comprises: modifying the content manifest to include the at least one unicast address of the content delivery node, the modification based at least on the information of the requesting device in the request for the content manifest.
 5. The method of claim 1 wherein serving the content manifest comprises: transmitting a redirect instruction to the requesting device, the redirect instruction comprising a Uniform Resource Locator (URL) representing a unicast address for a unicast manifest server of the network, the redirect instruction based at least on the information of the requesting device in the request for the content manifest.
 6. The method of claim 3 wherein the information of the requesting device comprises an Internet Protocol (IP) address of the requesting device.
 7. The method of claim 6 further comprising: accessing a database of IP addresses and associated estimated geographic locations, wherein the selecting of the content manifest to the requesting device is further based on an estimated geographic location associated with the IP address of the requesting device.
 8. The method of claim 1 wherein the information of the requesting device comprises at least one of an operating system of the requesting device, a type of the requesting device, a type of connection between the requesting device and the particular serving node, or a speed of the connection between the requesting device and the particular serving node.
 9. A content delivery network (CDN) comprising: a particular serving node associated with an anycast address receiving a request for a content manifest, the particular serving node being one of a plurality of serving nodes associated with the anycast address and the request comprising information of a requesting device in communication with the particular serving node, identifying a separate unicast manifest device based on the information of the requesting device in the request, the separate unicast manifest device being one of a plurality of content manifest devices, and redirecting the request to the separate unicast manifest device; the separate unicast manifest device serving a content manifest to the requesting device, the content manifest based on the information of the requesting device in the request, the content manifest comprising at least one unicast address of a content delivery node suitable for delivering the content to the requesting device.
 10. The CDN of claim 9 further comprising: a domain name service (DNS) infrastructure storing the anycast address for the content manifest associated with the content.
 11. The CDN of claim 9 wherein serving the content manifest comprises selecting the content manifest from a plurality of content manifests associated with the content, the selection based on the information of the requesting device in the request for the content manifest.
 12. The CDN of claim 11 wherein serving the content manifest further comprises modifying the selected content manifest to include the at least one unicast address of the unicast content server, the modification based at least on the information of the requesting device in the request for the content manifest.
 13. The CDN of claim 9 further comprising: a unicast manifest server available at a unicast address; and wherein serving the content manifest comprises transmitting a redirect instruction to the requesting device comprising the unicast address for the unicast manifest server, the redirect instruction based at least on the information of the requesting device in the request for the content manifest.
 14. The CDN of claim 11 wherein the information of the requesting device comprises an Internet Protocol (IP) address of the requesting device.
 15. The CDN of claim 14 further comprising: a database of IP addresses and associated estimated geographic locations; and wherein the serving of the content manifest to the requesting device is further based on an estimated geographic location associated with the IP address of the requesting device.
 16. The CDN of claim 9 wherein the information of the requesting device comprises at least one of an operating system of the requesting device, a type of the requesting device, a type of connection between the requesting device and the particular serving node, or a speed of the connection between the requesting device and the particular serving node. 